FIG. 6.

Polymer-salt coexistence phase diagrams of ${\text{Ddx}4}_{\mathrm{p}\mathrm{H}\mathrm{7}}^{\mathrm{N}\mathrm{1}}$ at the l/l_B values indicated. The salt-free critical value of l/l_B is $l/{\left(l_B\right)}_{\mathrm{c}\mathrm{r}}=0.455$. Top gray circles in (a)–(c) provide the upper critical salt concentrations ${\left({\varphi }_s\right)}_{\mathrm{c}\mathrm{r}}^{\mathrm{U}}$, whereas the bottom gray circle in (c) provides the lower critical concentration ${\left({\varphi }_s\right)}_{\mathrm{c}\mathrm{r}}^{\mathrm{L}}$ (see discussion in main text). Each dashed line in (a)–(c) is a tie line connecting a pair of coexistent phases. The three phase boundaries in (a)–(c) are compared in (d).